A dissection of the aorta is categorized based on the site of an original intimal tear. A Type A dissection is one which starts in the ascending aorta and may extend to the aortic arch, and possibly the descending aorta. A potential problem with a type A dissection is that it can progress proximally to the heart and may cause problems with heart rhythm.
Treatment involves isolating the heart from the dissected aorta while at the same time providing a blood flow path to the aortic arch and the descending aorta.